1. Field
The present disclosure relates to an energy storage device, a transport apparatus, and a control method.
2. Description of the Related Art
Japanese Unexamined Patent Application Publication No. 2014-082857 discloses a power supply system to be installed in a vehicle, the system charging a plurality of energy storage devices by using an external power source. The power supply system includes a first energy storage device that is a power source to an electrical load, the electrical load being a drive source of the vehicle; a converter configured to bidirectionally adjust a voltage between the first energy storage device and the electrical load; a second energy storage device that is connected to the converter in parallel; a charging device connected to the second energy storage device in parallel, the charging device being configured to charge at least one of the first energy storage device and the second energy storage device by using the power source outside the vehicle; and a control device configured to control the converter in such a manner that the first energy storage device is charged by using power from the second energy storage device and power from the charging device. When remaining energy of the second energy storage device is lower than a threshold, the control device causes the second energy storage device to be charged by using the charging device prior to charging of the first energy storage device. Then, as a result of charging of the first energy storage device by using power from the second energy storage device and power from the charging device, when the remaining energy of the second energy storage device is lower than the threshold, the control device again causes the second energy storage device to be charged by using the charging device.